bonjour
162 = 2 x 81
81 = 3 x 27
27 = 3 x 9
9 = 3 x 3
3 = 3 x 1
162 = 2 x 3 ⁴
108 = 2 x 54
54 = 2 x 27
27 = 3 x 9
9 = 3 x 3
3 = 3 x 1
108 = 2² * 3 ³
tu as la décomposition qui te permet de voir les diviseurs communs
a = 3 ⁴ x 7
a = 81 x 7 = 567
b = 2 x 3 ⁵ x 7 ²
b = 2 x 243 x 49 = 23 814
23 814 = 42 x 567 + 0 donc il a raison